D2565 - Recommended Practice For Operating Xenon-Arc Light And Water Exposure Apparatus Plastics.The weathershed of the Post Insulators shall be manufactured from either Hydrated Alumina Ethylene Propylene Copolymer (EPM) as the primary constituent or Silicone Elastomers. The weathershead shall be injection moulded and brought to final cure state in one continuous process to prevent internal undercure or surface overcure. Additionally, the weathershead shall provide hydrophobic surface, even after exposure to tropical marine environment, ultra violent rays and moisture.Core

The rod or the core is manufactured from Fibreglass, having 70-75 by weight of auxiliary aligned glass fibre bonded by an organic resin. The rod is either be cast or pultruded.The end fittings are have the following properties:

i. are compressed onto the Fibreglass rod memberii. are not move relative to the central Fibreglass rod at applied loads equal to two times the rated Routine Test Load or maximum designed cantilever loadsiii. are attracted to the rod after completion of all external heat processes used to cure or bond component parts.

The insulator are provided load limiting bases that will deform under longitudinal loading of more than 100% of the rated design cantilever load. Performance Characteristics

The Polymeric Insulators are meet the under listed performance characteristics.

ITEM

11kV

33KV

Dry Flashover Withstand

90kV

180kV

Wet flashover withstand

70kV

165kV

Positive Impulse Critical flashover

145kV

300kV

Maximum Radio Interference Voltage

Below 1micro volt

Below 1 micro volt

Design Tension Strength

100kN

100kN

Residual Strength after Power Arc

80kN

80kN

Mechanical Proof Test Load

45kN

45kN

Maximum Sustained Load

34kN

34kN

Design Torque Rating

83 Nm

83 Nm

The insulator are suitable for accepting both aluminium and copper conductors having cross-sectional areas ranging from 35mm2 to 265mm2. The insulators are designed for mounting on the angle and channel crossarms specified in Specification E14

All exposed ferrous part shall be treated against corrosion. Treatment by hot dip galvanizing is preferable.